<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>AJAX POST 请求</title>
    <style>
        #result{
            width: 200px;
            height: 100px;
            border: solid 1px #666;
        }
    </style>
</head>
<body>
    <div id = 'result'></div>
    <script>
        // 获取元素对象
        const result = document.getElementById('result');
        result.addEventListener("mouseover", function(){
            // console.log("test");
            // 1. 创建对象
            const xhr = new XMLHttpRequest();
            // 2. 初始化 设置请求类型 与 URL
            xhr.open('POST', 'http://127.0.0.1:8000/server');
            // 设置请求头
            xhr.setRequestHeader('Content-Type','application/x-www-form-urlencoded');
            xhr.setRequestHeader('name','zane')
            // 3. 发送 (POST可以添加参数查询字符串)
            // xhr.send('a=100&b=200&c=300');
            xhr.send("a:100&b:200&c:300")
            // xhr.send('666666666666');
            // 4. 事件绑定
            xhr.onreadystatechange = function(){
                // 判断
                if(xhr.readyState === 4){
                    if(xhr.status >= 200 && xhr.status < 300){
                        // 处理服务端返回结果
                        result.innerHTML = xhr.response;
                    }
                }
            }
        })
    </script>
</body>
</html>